4coder-non-source/test_data/lots_of_files/jam_audio.cpp

125 lines
2.9 KiB
C++

/*
* Overreact - Mr. 4th Dimention
* Allen Webster
* 03.21.2015 (mm.dd.yyyy)
*
* Audio Layer.
*/
internal void
wav_open_file(char *filename, Wav_File *wav_file){
File file = system_load_file(filename);
if (file.data && file.size > sizeof(Wav_File)){
*wav_file = {};
wav_file->file = file;
wav_file->header = *(Wav_Header*)file.data;
Assert(wav_file->header.chunk.id == WAV_CHUNK_RIFF);
Assert(wav_file->header.wav_id == WAV_CHUNK_WAVE);
}
}
internal i32
wav_data_requirement(Wav_File *wav_file){
u8 *cursor = (u8*)wav_file->file.data + sizeof(Wav_Header);
u64 size = wav_file->file.size;
u8 *end = (u8*)wav_file->file.data + size;
i32 requirement = 0;
i32 channels = 0;
while (1){
Wav_Chunk chunk;
chunk = *(Wav_Chunk*)cursor;
if (chunk.id == WAV_CHUNK_data){
Assert(requirement == 0);
requirement = chunk.size;
cursor += sizeof(Wav_Chunk) + chunk.size;
if (chunk.size % 2 == 1){
++cursor;
}
}
else{
if (chunk.id == WAV_CHUNK_fmt){
Wav_Format_Chunk_16 fmt;
fmt = *(Wav_Format_Chunk_16*)(cursor);
channels = fmt.channels;
}
cursor += sizeof(Wav_Chunk) + chunk.size;
}
if (cursor >= end){
break;
}
}
return requirement*(2/channels) + 4;
}
internal bool32
wav_fill_sound(Wav_File *wav_file, Sound *sound,
i32 system_sample_per_second){
u8 *cursor = (u8*)wav_file->file.data + sizeof(Wav_Header);
u64 size = wav_file->file.size;
u8 *end = (u8*)wav_file->file.data + size;
bool32 found_data = 0;
while (1){
Wav_Chunk chunk;
chunk = *(Wav_Chunk*)cursor;
if (chunk.id == WAV_CHUNK_data){
Assert(found_data == 0);
found_data = 1;
sound->memory_size = chunk.size*(2/sound->channels);
sound->sample_count = (chunk.size/sound->channels)/sound->bytes_per_sample;
i16 *sample_src = (i16*)(cursor + sizeof(Wav_Chunk));
i16 *sample_dest = sound->samples;
if (sound->channels == 1){
for (i32 i = 0; i < sound->sample_count; ++i){
*sample_dest++ = *sample_src;
*sample_dest++ = *sample_src++;
}
*sample_dest++ = 0;
*sample_dest++ = 0;
}
else{
for (i32 i = 0; i < sound->sample_count; ++i){
*sample_dest++ = *sample_src++;
*sample_dest++ = *sample_src++;
}
*sample_dest++ = 0;
*sample_dest++ = 0;
}
cursor += sizeof(Wav_Chunk) + chunk.size;
if (chunk.size % 2 == 1){
++cursor;
}
}
else{
if (chunk.id == WAV_CHUNK_fmt){
Wav_Format_Chunk_16 fmt;
fmt = *(Wav_Format_Chunk_16*)(cursor);
Assert(fmt.channels == 1 || fmt.channels == 2);
sound->channels = fmt.channels;
sound->samples_per_second = fmt.samples_per_second;
sound->bytes_per_sample = fmt.bits_per_sample >> 3;
sound->scan_speed = ((real32)sound->samples_per_second/system_sample_per_second);
}
cursor += sizeof(Wav_Chunk) + chunk.size;
}
if (cursor >= end){
break;
}
}
return found_data;
}